From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 870E2C433E0 for ; Mon, 1 Mar 2021 21:32:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A38160241 for ; Mon, 1 Mar 2021 21:32:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241104AbhCAVcE (ORCPT ); Mon, 1 Mar 2021 16:32:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:36400 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238019AbhCARSZ (ORCPT ); Mon, 1 Mar 2021 12:18:25 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 40F6464D9E; Mon, 1 Mar 2021 16:46:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614617202; bh=VMFUm4Hnw2KI51sSxLL0u3mOSVdwpmD1Jfzca45bw2s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WccSXPzJYn04nNQCV9YLmiyNfxMI/SSzZrAFB/Wo6grx7k9OtrBWbnrEhJRdQnPnn dhVJxLW5+S+t7fmc/CHFi7WJuGrihzmySd9nSL/kMkn/z5kF451Q/NivJj/qnotR27 bZQN0tMVPlfN/hvKErnOrtmZNzjZFM5Nm/z7sy8E= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Jason A. Donenfeld" , Florian Westphal , "David S. Miller" Subject: [PATCH 4.19 239/247] icmp: introduce helper for natd source address in network device context Date: Mon, 1 Mar 2021 17:14:19 +0100 Message-Id: <20210301161043.407029143@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161031.684018251@linuxfoundation.org> References: <20210301161031.684018251@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jason A. Donenfeld commit 0b41713b606694257b90d61ba7e2712d8457648b upstream. This introduces a helper function to be called only by network drivers that wraps calls to icmp[v6]_send in a conntrack transformation, in case NAT has been used. We don't want to pollute the non-driver path, though, so we introduce this as a helper to be called by places that actually make use of this, as suggested by Florian. Signed-off-by: Jason A. Donenfeld Cc: Florian Westphal Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/linux/icmpv6.h | 6 ++++++ include/net/icmp.h | 6 ++++++ net/ipv4/icmp.c | 33 +++++++++++++++++++++++++++++++++ net/ipv6/ip6_icmp.c | 34 ++++++++++++++++++++++++++++++++++ 4 files changed, 79 insertions(+) --- a/include/linux/icmpv6.h +++ b/include/linux/icmpv6.h @@ -31,6 +31,12 @@ static inline void icmpv6_send(struct sk } #endif +#if IS_ENABLED(CONFIG_NF_NAT) +void icmpv6_ndo_send(struct sk_buff *skb_in, u8 type, u8 code, __u32 info); +#else +#define icmpv6_ndo_send icmpv6_send +#endif + extern int icmpv6_init(void); extern int icmpv6_err_convert(u8 type, u8 code, int *err); --- a/include/net/icmp.h +++ b/include/net/icmp.h @@ -47,6 +47,12 @@ static inline void icmp_send(struct sk_b __icmp_send(skb_in, type, code, info, &IPCB(skb_in)->opt); } +#if IS_ENABLED(CONFIG_NF_NAT) +void icmp_ndo_send(struct sk_buff *skb_in, int type, int code, __be32 info); +#else +#define icmp_ndo_send icmp_send +#endif + int icmp_rcv(struct sk_buff *skb); void icmp_err(struct sk_buff *skb, u32 info); int icmp_init(void); --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -755,6 +755,39 @@ out:; } EXPORT_SYMBOL(__icmp_send); +#if IS_ENABLED(CONFIG_NF_NAT) +#include +void icmp_ndo_send(struct sk_buff *skb_in, int type, int code, __be32 info) +{ + struct sk_buff *cloned_skb = NULL; + enum ip_conntrack_info ctinfo; + struct nf_conn *ct; + __be32 orig_ip; + + ct = nf_ct_get(skb_in, &ctinfo); + if (!ct || !(ct->status & IPS_SRC_NAT)) { + icmp_send(skb_in, type, code, info); + return; + } + + if (skb_shared(skb_in)) + skb_in = cloned_skb = skb_clone(skb_in, GFP_ATOMIC); + + if (unlikely(!skb_in || skb_network_header(skb_in) < skb_in->head || + (skb_network_header(skb_in) + sizeof(struct iphdr)) > + skb_tail_pointer(skb_in) || skb_ensure_writable(skb_in, + skb_network_offset(skb_in) + sizeof(struct iphdr)))) + goto out; + + orig_ip = ip_hdr(skb_in)->saddr; + ip_hdr(skb_in)->saddr = ct->tuplehash[0].tuple.src.u3.ip; + icmp_send(skb_in, type, code, info); + ip_hdr(skb_in)->saddr = orig_ip; +out: + consume_skb(cloned_skb); +} +EXPORT_SYMBOL(icmp_ndo_send); +#endif static void icmp_socket_deliver(struct sk_buff *skb, u32 info) { --- a/net/ipv6/ip6_icmp.c +++ b/net/ipv6/ip6_icmp.c @@ -45,4 +45,38 @@ out: rcu_read_unlock(); } EXPORT_SYMBOL(icmpv6_send); + +#if IS_ENABLED(CONFIG_NF_NAT) +#include +void icmpv6_ndo_send(struct sk_buff *skb_in, u8 type, u8 code, __u32 info) +{ + struct sk_buff *cloned_skb = NULL; + enum ip_conntrack_info ctinfo; + struct in6_addr orig_ip; + struct nf_conn *ct; + + ct = nf_ct_get(skb_in, &ctinfo); + if (!ct || !(ct->status & IPS_SRC_NAT)) { + icmpv6_send(skb_in, type, code, info); + return; + } + + if (skb_shared(skb_in)) + skb_in = cloned_skb = skb_clone(skb_in, GFP_ATOMIC); + + if (unlikely(!skb_in || skb_network_header(skb_in) < skb_in->head || + (skb_network_header(skb_in) + sizeof(struct ipv6hdr)) > + skb_tail_pointer(skb_in) || skb_ensure_writable(skb_in, + skb_network_offset(skb_in) + sizeof(struct ipv6hdr)))) + goto out; + + orig_ip = ipv6_hdr(skb_in)->saddr; + ipv6_hdr(skb_in)->saddr = ct->tuplehash[0].tuple.src.u3.in6; + icmpv6_send(skb_in, type, code, info); + ipv6_hdr(skb_in)->saddr = orig_ip; +out: + consume_skb(cloned_skb); +} +EXPORT_SYMBOL(icmpv6_ndo_send); +#endif #endif